22 sure is a popular caliber, but I have doubts about it being the most produced. I'd bet that Colt has produced more 45's than all the 22's put together.

More 22 lr ammo has been produced than any other round. What percentage is shot in handguns is anyones guess.All handgun makers have made a lot more .22s than any other caliber.World wide a lot more 9mm have been made then .45s.I like .45s, but your statement is wrong.

Due to the world-wide use of the 9mm, I would guess that it is the most commonly produced. That said, the .45 ACP has to be a very close second.

In regards to the 32 ACP, there are at least several other pistol cartridges that are more common (9mm, .45 ACP, 38 Spl. .357 Magnum, 380, etc.)

The 22 LR was not designed as a "pistol" cartridge... instead, it introduced as a rifle cartridge, and in later years (much later), it was adapted to function in a handgun. The 9mm, .45 ACP, 38 Spl. .357 Magnum, and 380, are undoubtedly more common that the 22 LR in all of the many handguns produced worldwide.

Due to the world-wide use of the 9mm, I would guess that it is the most commonly produced. That said, the .45 ACP has to be a very close second.

In regards to the 32 ACP, there are at least several other pistol cartridges that are more common (9mm, .45 ACP, 38 Spl. .357 Magnum, 380, etc.)

The 22 LR was not designed as a "pistol" cartridge... instead, it introduced as a rifle cartridge, and in later years (much later), it was adapted to function in a handgun. The 9mm, .45 ACP, 38 Spl. .357 Magnum, and 380, are undoubtedly more common that the 22 LR in all of the many handguns produced worldwide.